Mo. farmers working to reduce dead zone in Gulf of Mexico

By by Jessica Machetta, (audio)
23 June 2011

The National Oceanic and Atmospheric Adminstration says this year’s floods will lead to a bigger than usual fish kill in the Gulf of Mexico. A University of Missouri agriculture expert says fertilizer run-off is a big contributor, and his studies are helping to curb the problem. Jessica Machetta reports.

Gene Stevens with the University of Missouri Delta Research Center says fertilizer run-off from crops causes algae blooms and red tide which causes fish to die from hypoxia — lack of oxygen.
NOAA predicts that because of flooding this year, the low-oxygen, or hypoxic region in the Gulf will equal the size of New Jersey and Delaware combined — nearly 10,000 square miles. “City-sized portions of this region could see oxygen levels in the water column dropping to zero,” marine scientists with NOAA report.
Even in non-flood years, nutrient run-off is a problem, and Stevens and his research team have developed software to keep fertilizer use to a minimum. The software calculates the minimum amount of fertilizer farmers need to use to still produce the maximum yield from crops.
The Midwest agriculture industry and the Gulf Coast aquaculture industry are intrinsicly linked, and Stevens says everyone needs to take a global outlook and approach to figure out how to best feed the world.
His team is also working to implement a system where wheat and cotton crops are planted together but in different seasons, so that the root stock after harvest helps hold the soil — and the nutrients — in place.
Stevens’ extension program helps educate commercial growers on innovative production practices that will increase the profitability of their field crop enterprises. Emphasis is placed on soil fertility and soil management inputs. Several research interests are in-field plant nutrient monitoring, liming in conservation tillage systems, and confinement practices for pharmaceutical crops.
This year’s forecast estimates that the size of the low-oxygen or hypoxic region in the Gulf will reach up to 9,421 square miles, the size of New Jersey and Delaware combined.

Oceanographers from the Louisiana Universities Marine Consortium, Louisiana State University, and the University of Michigan use nutrient inputs compiled from the U.S. Geological Survey’s extensive stream gauge network along the Mississippi River to forecast the marine biogeochemical reaction to the uploads of nitrogen and phosphorus into the Gulf of Mexico. In May 2011, the Mississippi watershed’s nitrogen transport into the Gulf was 35 percent higher than the average for that month over the last 32 years.